On 7/30/12 11:10 AM, James Graham wrote:
I don't think I have a strong opinion about what should happen here, but the Gecko behaviour could be easier to implement, and the WebKit behaviour slightly safer (presumably the point of this anomaly is to prevent infinite loops in load event handers).
In Gecko's case, the only thing like that I know of is that onload fires synchronously in Gecko in some cases, I believe. So we had to put in some sort of recursion guard to prevent firing onload on a parent in the middle of a child firing onload or something like that. See <https://bugzilla.mozilla.org/show_bug.cgi?id=330089>. Per spec, onload is always async, so this wouldn't be a concern.
I'm not quite sure what causes the behavior you're seeing in Gecko at <http://software.hixie.ch/utilities/js/live-dom-viewer/?saved=1686>, but at first glance it's sort of accidental... Which doesn't mean we shouldn't spec it, of course; it just means that figuring out what to spec is harder. :(
If desired, I can try to figure out exactly why there's only one load event on the first iframe there. Let me know.
-Boris
